Stretcher head rest

ABSTRACT

A vacuum pad suitable for use with a head rest of a stretcher is configured to support the head of a patient supported on the stretcher. The vacuum pad has a non-rigid state wherein the vacuum pad is formable and a rigid state wherein the vacuum pad is non-formable. The vacuum pad includes side walls with top edges positioned to lie at an elevation above the head rest. The top edges of the vacuum pad provide a wrist rest surface that is formable when the pad is in the non-rigid state.

This application is a divisional application of U.S. application, Ser.No. 09/782,826, filed Feb. 14 2001, and entitled “STRETCHER FOOT PEDAL”now U.S. Pat. No. 6,314,597, which is a divisional application of U.S.application, Ser. No. 09/369,546, filed Aug. 6, 1999, and entitled“ADJUSTABLE HEAD REST FOR A PATIENT SUPPORT” now U.S. Pat. No.6,249,923, which is a divisional application of U.S. application, Ser.No. 08/892,147, filed Jul. 14, 1997, and entitled “SURGICAL STRETCHER”now U.S. Pat. No. 6,076,208.

BACKGROUND AND SUMMARY OF THE INVENTION

The present invention relates to a surgical stretcher having a head restthat is adjustable relative to a back section of the stretcher. Moreparticularly, the present invention relates to a surgical stretcherhaving a head rest that provides increased stabilization of the head ofthe patient, which is desirable during some head surgeries.

Hospital stretchers having head rests that support the head of a patientduring head and neck surgery are known. See, for example, U.S. Pat. No.4,882,797 to Failor et al. Hospital stretchers having wrist rests thatsupport the wrists of a surgeon performing surgery on the head and neckof the patient are also known. See, for example, the Failor et al. '797patent and U.S. Pat. No. 4,390,011 to Evans.

According to the present invention, a head rest of a surgical stretcherincludes a vacuum pad configured to support the head of a patientsupported on the stretcher. The vacuum pad has a non-rigid state whereinthe vacuum pad is formable and a rigid state wherein the vacuum pad isnon-formable. The vacuum pad has side walls with top edges positioned tolie at an elevation above the head rest. The top edges of the vacuum padprovide a wrist rest surface that is formable when the vacuum pad is inthe non-rigid state.

Additional objects, features, and advantages of the invention willbecome apparent to those skilled in the art upon consideration of thefollowing detailed description of a preferred embodiment exemplifyingthe best mode of carrying out the invention as presently perceived.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description particularly refers to the accompanying figuresin which:

FIG. 1 is a perspective of a surgical stretcher in accordance with thepresent invention showing a patient support deck having a head end and afoot end, a head rest coupled to the head end of the patient-supportdeck, and extender boards mounted to sides of the patient-support deck,each of the extender boards being pivotable between a first positionadjacent to the head rest and a second position extending toward thefoot end of the patient-support deck;

FIG. 2 is top plan view of the surgical stretcher of FIG. 1 showing bothextender boards in their respective first positions adjacent to the headrest and showing one of the extenders pivoting through a transitionposition (in phantom) into the second position (in phantom) to functionas an arm board;

FIG. 3 is a rear elevation view of a back section of the patient-supportdeck of the stretcher of FIG. 1 in a substantially vertical positionshowing the back section having a tubular frame member defining theouter perimeter of the back section and a first releasing assemblycoupled to the back section, the first releasing assembly beingactuatable to unlock the back section for pivoting movement relative toa frame of the stretcher;

FIG. 4 is a view of the back section similar to FIG. 3, with portionsbroken away, showing one of the extender boards in the first positionand a second releasing assembly coupled to the extender board, thesecond releasing assembly being actuatable to unlock the back sectionfor pivoting movement relative to the frame of the stretcher;

FIG. 5 is a sectional view taken along line 5—5 of FIG. 4 showing alatch mounted to the extender board for movement between a lockingposition in which the extender board is locked in the first position anda releasing position (in phantom) in which the extender board isunlocked and can pivot relative to the back section;

FIG. 6 is a sectional view of a first embodiment connector assembly thatconnects each of the extender boards to one of a pair of rails attachedto the back section frame member showing the connector assemblyincluding two clutch disks overlying a clutch assembly that biases theclutch disks together in frictional engagement with one another;

FIG. 7 is an exploded perspective view of a second embodiment connectorassembly that connects each of the extender boards to the respectiverail showing the second embodiment connector assembly including twotoothed clutch disks overlying an assembly for clamping the clutch diskstogether;

FIG. 8 is a side elevation view of the surgical stretcher of FIG. 1showing the back section being locked in a flat table position by afirst gas spring connecting the back section to the frame of thestretcher, a bracket coupling the head rest to the back section, thebracket being locked relative to the back section by a second gas springconnecting the bracket to the back section, and the head rest beinglocked in generally coplanar relation with the back section by a springclutch connecting the head section to the bracket;

FIG. 9 is a view similar to FIG. 8 showing the bracket tilted downwardlyrelative to the back section, the head rest tilted rearwardly relativeto the bracket, the bracket being pivotable relative to the back sectionabout a transverse horizontal first pivot axis when the second gasspring is unlocked, and the head rest being pivotable relative to thebracket about a transverse horizontal second pivot axis when the springclutch is unlocked;

FIG. 10 is a view similar to FIG. 9 showing the bracket tilted upwardlyrelative to the back section and the head rest tilted forwardly relativeto the bracket;

FIG. 11 is a perspective view of the head rest and bracket of FIG. 10showing a head rest cushion filler above the head rest, a portion of atemporal wrist rest assembly beside the head rest and coupleable to thehead rest, and release hardware coupled to the head rest and bracket,the release hardware being movable to simultaneously unlock the secondgas spring and the spring clutch so that the head rest and bracket canbe repositioned relative to the back section;

FIG. 12 is a perspective view of the head rest of FIG. 11 showing thehead rest having a flat bottom plate, a longitudinally-extending sockettube appended to each side of the bottom plate, a side plate anglingupwardly from each socket tube, and a transversely-extending bar of thetemporal wrist rest assembly projecting underneath the head rest;

FIG. 13 is a view similar to FIG. 12 showing a wrist rest assemblycoupled to the head rest by longitudinally-extending rods, each rodbeing received by a respective socket tube of the head rest, a wire griphandle coupled to the head rest beneath the bottom plate thereof, and arelease button that can be pressed to unlock the second gas spring andthe spring clutch, the release button being positioned to lie between aside handle portion of the wire grip handle and the head rest;

FIG. 14 is a bottom plan view of a portion of the wrist rest assembly,with portions broken away showing a transversely-extending end tubehaving a portion received in the interior region of an end socket tubeand a turn screw coupled to both the end tube and the end socket tube;

FIG. 15 is a perspective view of the head rest showing an air manifoldassembly coupled to a U-shaped wrist rest of the wrist rest assembly,the wrist rest and air manifold assembly being pivotable away from ahead of a patient to an out-of-the-way position (in phantom);

FIG. 16 is a side elevation view of the head rest of FIG. 15 showing theair manifold assembly and wrist rest assembly supporting a drape overthe head of the patient to create a tented environment;

FIG. 17 is a perspective view of the head rest of FIG. 1 showing avacuum pad being insertable between the head of the patient and the headrest, the vacuum pad having side walls with top edges that function aswrist rests;

FIG. 18 is top plan view of the vacuum pad of FIG. 17 in a flat uncuppedconfiguration showing the vacuum pad including a strap extending fromone side thereof;

FIG. 19 is a sectional view of the vacuum pad taken along line 19—19 ofFIG. 18 showing foam beads filling an interior region of the vacuum pad;

FIG. 20 is a perspective view of a head end lower portion of thesurgical stretcher of FIG. 1 showing a flip-over pedal coupled to alongitudinally-extending brake-steer shaft by a yoke, the yoke being inan upright neutral position, and the flip-over pedal being pivotable inthe direction of the double arrow relative to the yoke;

FIG. 21 is an end elevation view of the surgical stretcher of FIG. 20showing the yoke in the upright neutral position, the flip-over pedal ina first orientation relative to the yoke, and the yoke being movable inthe direction of the single arrow to pivot the brake-steer shaft about alongitudinally-extending axis in the direction of the single arrow;

FIG. 22 is a view similar to FIG. 21 showing the flip-over pedal andyoke in a steering position and the flip-over pedal being movablerelative to the yoke from the first orientation to a second orientation(in phantom); and

FIG. 23 is a view similar to FIG. 22 showing the flip-over pedal andyoke in a braking position and the flip-over pedal being movablerelative to the yoke from the second orientation back to the firstorientation (in phantom).

DETAILED DESCRIPTION OF THE DRAWINGS

A surgical stretcher 30 in accordance with the present inventionincludes a frame 32 and a patient-support deck 34 supported by frame 32as shown in FIG. 1. Patient-support deck 34 has a head end 36, a footend 38, and first and second longitudinal sides 40, 42 extending betweenhead end 36 and foot end 38. Stretcher 30 includes a mattress 44supported by patient-support deck 34. Mattress 44 has an upwardly-facingpatient-support surface 46 on which a patient can rest.

Stretcher 30 includes a head rest 48 adjacent to head end 36 ofpatient-support deck 34. Head rest 48 is coupled to a back section 50 ofpatient-support deck 34 and the position of head rest 48 can be adjustedrelative to back section 50. In addition, the position of back section50 can be adjusted relative to frame 32 and relative to the rest ofpatient-support deck 34. Head rest 48 includes a head cushion 52 thatsupports the head of the patient.

Stretcher 30 also includes a pair of extender boards 54, each of whichis mounted to respective first and second longitudinal sides 40, 42 ofback section 50 of patient-support deck 34. Each extender board 54supports a cushion 56 having an extension surface 58. Extender boards 54are independently pivotable relative to back section 50 between a firstposition adjacent to head rest 48, as shown in FIGS. 1 and 2, and asecond position extending away from back section 50 toward foot end 38of patient-support deck 34, as shown in FIGS. 1 and 2 (in phantom).Stretcher 30 includes a pair of side guard assemblies 61 that, whenmoved to a lowered position as shown in FIG. 1, permit full movement ofextender boards 54 between the first and second positions.

Stretcher 30 includes a lower frame (not shown) covered by a shroud 60as shown in FIG. 1. Casters 62 are mounted to the lower frame and extenddownwardly therefrom to engage a floor 64 on which stretcher 30 sets.Frame 32 and patient-support deck 34 are supported above the lower frameand shroud 60 by a pair of longitudinally spaced-apart elevationmechanisms (not shown), well-known to those skilled in the art. Theelevation mechanisms are each covered by a boot 66 as shown in FIG. 1.Stretcher 30 includes a plurality of foot pedals 68 that are coupled tothe elevation mechanisms. Different foot pedals 68 can be depressed sothat the elevation mechanisms are actuated to raise, lower, or tiltframe 32 and patient-support deck 34 relative to floor 64.

Stretcher 30 also includes a longitudinally-extending brake-steer shaft70. Brake-steer shaft 70 is coupled to a conventional caster brakingmechanism 71 which is shown diagrammatically in FIG. 20 and which iswell known to those skilled in the art. Caster braking mechanism 71brakes casters 62 to prevent them from rotating and swivelling whenbrake-steer shaft 70 is rotated to a braking position. Brake-steer shaft70 is also coupled to a conventional center wheel mechanism 73 which isalso shown diagrammatically in FIG. 20 and which is also well known tothose skilled in the art. Center wheel mechanism 73 lowers a centerwheel (not shown) into engagement with floor 64 when brake-steer shaft70 is rotated to a steering position.

A brake pedal 72 is coupled to brake-steer shaft 70 beneath foot end 38of patient-support deck 34 and a pedal assembly 74 is coupled tobrake-steer shaft 70 beneath head end 36 of patient-support deck 34.Brake pedal 72 can be engaged to rotate brake-steer shaft 70 to thebraking position, thereby braking casters 62. Pedal assembly 74 includesa yoke 76 and a flip-over pedal 78 coupled to yoke 76 for pivotingmovement. Flip-over pedal 78 is movable relative to yoke 76 between afirst orientation in which a distal end portion 80 can be engaged torotate brake-steer shaft 70 to the steering position and a secondorientation in which end portion 80 can be engaged to rotate brake-steershaft 70 to the braking position as will be discussed in detail belowwith reference to FIGS. 20-23.

Stretcher 30 is well suited for head and neck surgery, and particularly,for outpatient head and neck surgery. Prior to surgery, when the patientis resting on stretcher 30 in a pre-op waiting area, for example,extender boards 54 can be moved to the first position adjacent to headrest 48 so that extension surfaces 58 cooperate with patient-supportsurface 46 to increase the support surface area near the head andshoulders of the patient. Stretcher 30 can be used to transport thepatient from the pre-op waiting area to an operating room where surgeryis to be performed on the patient.

During transport, back section 50 can be placed in a desired positiondepending upon the preference of the caregiver or the patient. Forexample, if the patient is unconscious, back section 50 can be moved toa horizontal position in which the patient is supported in a lying-downposition. Alternatively, if the patient is conscious and capable ofsitting up, back section 50 can be moved to an inclined position inwhich back section 50 is angled at about seventy degrees (70°) relativeto frame 32, thereby placing the patient in a sitting-up position. Inaddition, back section 50 can be moved to any one of an infinite numberof intermediate positions between the horizontal and inclined positions,if desired.

During transport of the patient to the operating room, pedal assembly 74can be used to move brake-steer shaft 70 to the steering position havingthe center wheel engaging floor 64 to assist in steering stretcher 30 byproviding a frictional contact area with floor 64 about which stretcher30 can be easily turned. After stretcher 30 reaches the desired locationin the operating room, pedal assembly 74 can be used to move brake-steershaft 70 to the braking position so that casters 62 are prevented fromrotating or swivelling, thereby preventing stretcher 30 from movingalong floor 64.

Prior to surgery, back section 50 can be moved to the horizontalposition and one or both of extender boards 54 can be moved away fromhead rest 48 to their respective second positions. Placing each extenderboard 54 in the second position results in increased access to the headof the patient by the surgeon. In addition, extension surfaces 58 ofcushions 56 can support the arms of the patient out past sides 40, 42 ofpatient-support deck 34 so that IV fluids and anesthesia can beadministered to the patient during surgery. After the patient has beenanesthetized, the surgeon can move the head of the patient to a desiredsurgical position by adjusting the position of head rest 48.

After surgery, extender boards 54 can be returned to their firstpositions adjacent to head rest 48. Pedal assembly 74 can be used tomove brake-steer shaft 70 out of the braking position and into thesteering position and stretcher 30 can then be used to transport thepatient to a post-op area where the patient can recover from surgery.Thus, the patient can rest upon patient-support surface 46 of stretcher30 before, during, and after surgery. In addition, extender boards 54can be moved between first and second positions to function as headextenders and arm boards, respectively.

As previously described, back section 50 can be moved between horizontaland inclined positions. Back section 50 includes a tubular frame member82 having a base strut 84 as shown in FIG. 3. A pair of transverselyspaced-apart flanges 86 extend away from base strut 84 and couple torespective longitudinally-extending flanges 88 appended to a cross strut91 of frame 32. Flanges 86 are pinned to flanges 88 so that back section50 can pivot relative to frame 32 about a transverse pivot axis 92,shown, for example, in FIGS. 1-3.

Back section 50 includes a panel 94 attached to frame member 82. Panel94 of back section 50 includes a substantially planar surface 96 thatsupports part of mattress 44 as shown in FIG. 2. The part of mattress 44supported by surface 96 of panel 94 includes a back-support surface 47that engages the upper torso of the patient resting on mattress 44.

Frame member 82 includes a pair of spaced-apart longitudinal side struts98, a transverse end strut 100, and a pair of angled corner portions 110connecting side struts 98 to end strut 100 as shown best in FIG. 3. Sidestruts 98, end strut 100, and angled corner portions 110 are configuredso as to define a plane in which back section 50 is situated. A rail 112is coupled to each side strut 98 by a pair of spacers 114 that positionrails 112 in spaced-apart relation with respective side struts 98.

A connector assembly 116 is appended to each extender board 54.Connector assemblies 116 can be attached to rails 112, thereby couplingextender boards 54 to back section 50. When coupled to back section 50,extender boards 54 can pivot about a respective pivot axis 118 as shownin FIGS. 1 and 2. Each pivot axis 118 is substantially perpendicular tosurface 96 of panel 94 of back section 50.

Each extender board 54 includes a frame 120 and a panel 122 attached toframe 120. Panel 122 of each extender board 54 includes a top surface124 that supports cushion 56. As extender boards 54 pivot relative toback section 50, for example, in a direction 126 shown in FIGS. 1 and 2,surfaces 124 of panels 122 are maintained in substantially coplanarrelation with surface 96 of panel 94 and extension surfaces 58 ofcushions 56 are maintained in substantially coplanar relation withback-support surface 47 of mattress 44.

Frame 120 of each extender board 54 includes a long side portion 128, acorner portion 130 integrally appended to portion 128, a distal endportion 132 integrally appended to corner portion 130 in perpendicularrelation to portion 128, a mid-size side portion 134 appended to portion132 in parallel relation with portion 128, an angled portion 136extending away from portion 134 toward portion 128, and a short sideportion 138 integrally appended to portion 136 in parallel relation withportion 128 as shown best in FIG. 4. Portions 128, 130, 132, 134, 136,138 of frame 120 define the perimeter of extender boards 54. Panels 122extend between portions 128, 130, 132, 134, 136, 138 of respectiveframes 120.

Head rest 48 has first and second longitudinally-extending sides 140,142 and an end 144 connecting sides 140, 142. Sides 140, 142 of headrest 48 are spaced apart by a distance that is smaller than a distanceby which sides 40, 42 of patient-support deck 34 are spaced apart. Whenextender boards 54 are in their first positions, mid-size side portions134 of frames 120 are adjacent to the respective side 140, 142 of headrest 48, angled portions 136 of frames 120 are adjacent to therespective corner portion 110 of frame member 82, and short sideportions 138 of frames 120 are adjacent to the respective side struts 98of frame member 82. In addition, mid-size side portion 134 of each frame120 includes a docking portion 146 that extends toward and is adjacentto end strut 100 of frame member 82 of back section 50 when therespective extender board 54 is in the first position.

When extender boards 54 are in their first positions, distal endportions 132 of each frame 120 extend substantially transversely and aregenerally aligned with end 144 of head rest 48 as shown in FIG. 2. Inaddition, when extender boards 54 are in their first positions, sideportions 128, 134, and 138 are all substantially parallel with sidestruts 98 of frame member 82 of back section 50. Thus, when extenderboards 54 are in their first positions adjacent to head rest 48,extension surfaces 58 provide additional surface area on which the headand shoulders of the patient can rest.

Each extender board 54 can pivot about respective axes 118 from thefirst position to a second position in which portion 134 of frame 120 isno longer adjacent to the respective side 140, 142 of head rest 48.Extender boards 54 extend more toward foot end 38 of patient-supportdeck 34 than head end 36 of patient-support deck 34 when in the secondposition, as shown in FIGS. 1 and 2. Thus, when extender boards 54 arein their second positions, extension surfaces 58 can support the arms ofthe patient out past sides 40, 42 of patient-support deck 34.

As previously described, connector assemblies 116 couple each extenderboard 54 to a companion rail 112 and allow each extender board 54 topivot about a respective axis 118. The description below of one of theconnector assemblies 116 applies to the other of the connectorassemblies 116 as well.

Connector assembly 116 includes a slide block 148 having a rail-engagingportion 150 and a clutch plate 152 extending away from rail-engagingportion 150 as shown in FIG. 6. Rail-engaging portion 150 of slide block148 is generally C-shaped so as to define a channel 154 that receivesrail 112. Channel 154 of portion 150 is formed to allow longitudinalsliding movement of connector assembly 116 and the associated extenderboard 54 relative to rail 112.

Connector assembly 116 includes a threaded cylinder 156 appended to abottom corner portion of rail-engaging portion 150. A turn screw 158 isthreadedly coupled to cylinder 156. Turn screw 158 can be turned totighten slide block 148 against rail 112 to prevent connector assembly116 from sliding relative to rail 112. Turn screw 158 can also be turnedto loosen slide block 148 from rail 112 to allow connector assembly 116to slide relative to rail 112. Thus, connector assembly 116 and extenderboard 54 can be moved to a desired position along rail 112 and then turnscrew 158 can be turned to lock connector assembly 116 at the desiredposition.

Clutch plate 152 extends horizontally away from its companionrail-engaging portion 150 as shown in FIG. 6. A second clutch plate 160of connector assembly 116 is attached to extender board 54 and issupported by clutch plate 152. In addition, clutch plate 160 isconnected to clutch plate 152 by a bolt 162 that extends throughapertures 164, 166 formed in clutch plates 152, 160, respectively.

As extender board 54 pivots about axis 118, clutch plate 160 pivotsrelative to clutch plate 152. Bolt 162 includes a square-shaped lug 168and clutch plate 160 includes a square-shaped recess 170 that receiveslug 168 so that bolt 162 turns along with clutch plate 160 as clutchplate 160 is turned relative to clutch plate 152. Bolt 162 cooperateswith apertures 164, 166 of plates 152, 160 to define pivot axis 118.

Bolt 162 extends downwardly past clutch plate 152 and a clutch assembly172 is mounted to the downwardly-extending portion of bolt 162 as shownin FIG. 6. Clutch assembly 172 includes a lower self-lubricating washer176, a flat washer 174, and a set of three Belleville washers 178 thatbias flat washer 174 against lower self-lubricating washer 176. A nut180 threadedly engages bolt 162 so that clutch plates 152, 160 andclutch assembly 172 are clamped together, thereby loading washers 178.An upper self-lubricating washer 177 is sandwiched between clutch plates152, 160. The loading of washers 178 causes a top surface 182 of clutchplate 152 and a bottom surface 184 of clutch plate 160 to engage upperself-lubricating washer 177 with sufficient force to hold extender board54 at any desired position between the first and second positions,independent of the position of back section 50, while also allowingextender board 54 to be manually moved about axis 118 from one positionto another. Upper and lower self-lubricating washers 176, 177 can be,for example, oil-impregnated brass bushings supplied by OILITE™.

An alternative embodiment connector assembly 186 is shown in FIG. 7. Thedescription below of one of the connector assemblies 186 applies to theother of connector assemblies 186 as well. Connector assembly 186includes a slide block 188 having a rail-engaging portion 190 and aplate 192 extending away from rail-engaging portion 190 as shown in FIG.6. Rail-engaging portion 190 of slide block 188 is generally C-shaped soas to define a channel 194 that receives rail 112. Channel 194 ofportion 190 is formed to allow longitudinal sliding movement ofconnector assembly 186 and the associated extender board 54 relative torail 112.

Connector assembly 186 includes a threaded cylinder 196 appended to abottom corner portion of rail-engaging portion 190 and a turn screw 198threadedly coupled to cylinder 196. Turn screw 198 of connector assembly186 operates to prevent and allow sliding movement of connector assembly186 relative to rail 112 in a manner similar to the manner in which turnscrew 158 of connector assembly 116 operates to prevent and allowsliding movement of connector assembly 116 relative to rail 112.

A plurality of radially-extending upwardly-projecting teeth 210 isappended to plate 192 as shown in FIG. 7. Connector assembly 186includes a second plate 212 attached to extender board 54. A pluralityof radially-extending downwardly-projecting teeth 214 is appended toplate 212. Connector assembly 186 includes a clamping assembly 216 thatis movable between a locking position, in which teeth 210 mesh withteeth 214 to prevent pivoting movement of extender board 54 about pivotaxis 118, and a releasing position, in which teeth 210 do not mesh withteeth 214 to allow pivoting movement of extender board 54 about axis118.

Plate 192 is formed to include an aperture 218 and plate 212 is formedto include a threaded aperture 220 as shown in FIG. 7. Clamping assembly216 includes a bolt 222 having an end portion received by aperture 220and threadedly coupled to plate 212 so that bolt 222 rotates along withclutch plate 212 as clutch plate 212 pivots about axis 118 relative toclutch plate 192. Bolt 222 also includes a portion received by aperture218 for rotating movement. Bolt 222 cooperates with apertures 218, 220of plates 192, 212 to define pivot axis 118.

Bolt 222 includes a block portion 224 positioned to lie underneath plate192 as shown in FIG. 7. Connector assembly 186 includes a cylindricalspacer subassembly 226 between block portion 224 and plate 192. Inaddition, connector assembly 186 includes a lever 228 having a yoke 232,a knob 234, and a rod 236 connecting yoke 232 to knob 234. Yoke 232 oflever 228 is coupled to block portion 224 of bolt 222 by a pivot pin 230so that lever 228 can pivot relative to bolt 222 and plate 192. Yoke 232includes a pair of spaced-apart U-shaped locking edges 238 and a pair ofcurved edges 240 as shown in FIG. 7.

Lever 228 can be moved to a vertical releasing position in which curvedsurfaces 240 face substantially upwardly toward a bottom surface 242 ofspacer subassembly 226 as shown in FIG. 7. When lever 228 is in thereleasing position, extender board 54 can be lifted upwardly by a slightamount so that teeth 210 of plate 192 do not mesh with teeth 214 ofplate 212 and then extender board 54 can be pivoted about axis 118relative to back section 50. Thus, when lever 228 in the releasingposition, connector assembly 186 is in the releasing position and theposition of extender board 54 can be adjusted.

Lever 228 can pivot from the releasing position in a first directionindicated by arrow 244, shown in FIG. 7, to a first locking position inwhich one of locking edges 238 abuts bottom surface 242 of spacersubassembly 226. Lever 228 can also pivot from the releasing position ina second direction indicated by arrow 246, shown in FIG. 7, to a secondlocking position in which the other one of locking edges 238 abutsbottom surface 242 of spacer subassembly 226. When lever 228 is ineither the first locking position or the second locking position, plate212 is clamped against plate 192 so that teeth 210 mesh with teeth 214,thereby preventing extender board 54 from pivoting relative to backsection 50. Thus, when lever 228 is in either the first or the secondlocking position, connector assembly 186 is in the locking position andextender board 54 is locked in place relative to back section 50.

Spacer subassembly 226 includes a cylinder 248 beneath clutch plate 192,a washer 250 beneath cylinder 248, and a hard rubber washer 252sandwiched between washer 250 and cylinder 248. As lever 228 is movedbetween the releasing position and either of the first or second lockingpositions, rubber washer 252 is compressed as washer 250 is forcedtoward cylinder 252 by lever 228. When lever 228 is in either the firstor the second locking position, rubber washer 252 is held in compressionso that washer 250 acts through lever 228 and bolt 222 to bias plate 212against plate 192. The compression of rubber washer 252 also biaseswasher 250 against one or the other of edges 238 of yoke 232. Biasing ofone of edges 238 with washer 250 holds lever 228 in the respective firstor second locking position.

As previously described, frame 120 of each extender board 54 includes adocking portion 146. Stretcher 30 includes a pair of posts 254 coupledto end strut 100 of frame member 82 of back section 50. Posts 254 extendlongitudinally away from end strut 100 as shown, for example, in FIG. 3.Each docking portion 146 is essentially a square-shaped tube having awindow 256 cut out of one of the sides so that posts 254 can be receivedinside docking portions 146. When extender boards 54 are pivoted intotheir first positions, posts 254 pass through windows 256 so that a sidewall 258 of each docking portion 146 can engage a first side 253 ofrespective posts 254 to locate extender boards 54 in their firstpositions.

If extender boards 54 are coupled to back section 50 by connectorassemblies 116, stretcher 30 can include a latch assembly 260 coupled toan undersurface 262 of panel 122 of extender boards 54 as shown in FIGS.4 and 5. The description below of one of latch assemblies 260 isdescriptive of both latch assemblies 260.

Latch assembly 260 includes a bracket 264 that attaches to undersurface262 of panel 122 and a latch plate 266 having a pair of central flanges268 pinned to bracket 264. Latch assembly 260 also includes a torsionspring 270 that engages undersurface 262 of panel 122 and latch plate266 to bias latch plate 266 into a locking position as shown in FIG. 5.

Latch plate 266 includes an upturned tab 272 having a locking edge 274and a cam edge 276 as shown in FIG. 5. When latch plate 266 is in thelocking position and extender board 54 is in the first position, lockingedge 274 of tab 272 engages a second side 255 of post 254 so thatextender board 54 is locked in the first position. Latch plate 266includes a hand-engaging portion 278 adjacent to long side portion 128of frame 120 as shown in FIG. 4. Hand-engaging portion 278 of latchplate 266 can be moved in a direction indicated by a double arrow 280,shown in FIG. 5, toward undersurface 262 of panel 122 to move latchplate 266 from the locking position to a releasing position, shown inFIG. 5 (in phantom). When latch plate 266 is in the releasing position,locking edge 274 is spaced apart from second side 255 of post 254allowing extender board 54 to be moved out of the first position towardthe second position.

When extender board 54 is moved from the second position back to thefirst position, cam edge 276 of tab 272 ramps against post 254 toautomatically move latch plate 266 from the locking position to thereleasing position allowing extender board 54 to be moved all the wayinto the first position. After extender board 54 reaches the firstposition having side wall 258 of docking portion 146 engaging first side253 of post 254, torsion spring 270 urges latch plate 266 back into thelocking position so that extender board 54 is locked in the firstposition. Thus, engagement of first side 253 of post 254 with side wall258 of docking portion 146 prevents extender board 54 from pivoting pastthe first position toward head rest 48 and engagement of locking edge274 of latch plate 266 prevents extender board 54 from pivoting out ofthe first position away from head rest 48.

A locator post 281 is coupled to and extends away from each of rails 112as shown in FIG. 2. When each connector assembly 116 is mounted to therespective rail 112 by sliding rail-engaging portion 150 of slide block148 onto rail 112 in a direction toward foot end 38 of patient-supportdeck 34, engagement of slide block 148 with post 281 places connectorassembly 116 at the proper location so that docking portion 146 of frame120 of extender board 54 will engage post 254 when extender board 54 ismoved to the first position. Locator posts 281 serve this same functionwhen extender boards 54 are coupled to rails 112 by connector assemblies186 rather than connector assemblies 116. Rails 112 each have sufficientlength to allow other medical equipment, such as IV poles, to be mountedto rails 112 even when extender boards are coupled to rails 112.

As previously described, back section 50 can pivot about axis 92 betweenhorizontal and inclined positions and can be situated in an infinitenumber of intermediate positions between the horizontal and inclinedpositions. Stretcher 30 includes an actuator 282 having a first end 284pivotably coupled to a pair of flanges 286 as shown in FIG. 3. Flanges286 are coupled to cross strut 90 of frame 32 and first end 284 ofactuator 282 is coupled to flanges 286 by a pin 290. Actuator 282 has asecond end 292 coupled to a pivot block 294 which is pivotably coupledby a pin 297 to a pair of flanges 295 extending from end strut 100 offrame member 82 as shown in FIGS. 3 and 4. Actuator 282 is releasable sothat back section 50 can pivot about axis 92 relative to frame 32 andactuator 282 is lockable so that back section 50 is prevented frompivoting about axis 92 relative to frame 32.

In a preferred embodiment, actuator 282 is a gas spring (hereinafterreferred to as gas spring 282) although it is within the scope of theinvention as presently perceived for actuator 282 to include any lockingmechanism that can extend and retract and that can be locked to preventmovement of the actuator. Thus, the term “actuator” as used in thisspecification and in the claims includes a gas spring, a spring clutch,a ball screw, a hydraulic cylinder, a pneumatic cylinder, or any othersuitable mechanism that can be locked to prevent back section 50 frompivoting relative to frame 32 and that can be released to allow backsection 50 to be grabbed and manually pivoted relative to frame 32.

Gas spring 282 includes a housing 296, a piston (not shown) insidehousing 296, and a piston rod 298 coupled to the piston and extendingout of housing 296. Housing 296 is coupled to flanges 286 and piston rod298 is coupled to pivot block 294. Gas spring 282 can be locked so thatthe piston and piston rod 298 are generally fixed relative to housing296 so that piston rod 298 can neither extend further out of housing 296nor retract into housing 296, thereby preventing back section 50 frompivoting about axis 92 relative to frame 32. Gas spring 282 can also bereleased so that the piston can move and piston rod 298 can extend andretract relative to housing 296, thereby allowing back section 50 to begrabbed and pivoted about axis 92 relative to frame 32.

Gas spring 282 includes a plunger 300 extending out of piston rod 298 asshown in FIGS. 3 and 4. Plunger 300 has an extended locking position inwhich gas spring 282 is locked preventing back section 50 from pivotingrelative to frame 32. Plunger 300 also has a plunged releasing positionin which gas spring 282 is released allowing back section 50 to pivotrelative to frame 32. Plunger 300 is biased into the extended lockingposition so that gas spring 282 is normally locked.

Stretcher 30 includes a release rod 310 that can be actuated to moveplunger 300 from the locking position to the releasing position. Pivotblock 294 is formed to include a channel 312 and release rod 310includes a middle portion 314 received within channel 312. Channel 312extends generally transversely through pivot block 294 along a V-shapedpath defined by first and second angled side walls 316, 318 and a bottomside wall 320 having chamfered corner portions. Middle portion 314 ofrelease rod 310 is bent so that middle portion 314 is trapped withinchannel 312 by side walls 316, 318, 320 of pivot block 294, therebypreventing release rod 310 from moving transversely relative to backsection 50. A plate 321 is attached to pivot block 294 to cover channel312, thereby preventing release rod 310 from falling out of channel 312.

Release rod 310 includes straight portions 322 that extend transverselyaway from middle portion 314 beyond pivot block 294 toward respectivefirst and second sides 40, 42 of back section 50. Release rod 310 alsoincludes first and second handle portions 324, 326 that are eachsituated in the plane of back section 50 adjacent to respective cornerportions 110 of frame member 82 as shown in FIG. 3. Handle portions 324,326 angle away from straight portions 322 so that handle portions 324,326 are generally parallel with corner portions 110 of frame member 82.A soft handle cover 328 is attached to each of handle portions 324, 326to provide a comfortable feel to handle portions 324, 326.

Panel 94 is cut out in the region adjacent to corner portions 110 andhandle portions 324, 326 to allow access to handle portions 324, 326from above back section 50 and from below back section 50. Handleportions 324, 326 are in close proximity to respective corner portions110 of frame member 82 so that the caregiver or the surgeon cansimultaneously grasp one of corner portions 110 and one of handleportions 324, 326.

Handle portion 324 can be squeezed toward the adjacent corner portion110 of frame member 82 to move plunger 300 from the locking position tothe releasing position or, alternatively, handle portion 326 can besqueezed toward the adjacent corner portion 110 of frame member 82 tomove plunger 300 from the locking position to the releasing position.Thus, release rod 310 and pivot block 294 cooperate to provide stretcher30 with a releasing assembly that can be actuated to adjust the positionof back section 50.

When handle portion 324 is squeezed toward the adjacent corner portion110, release rod 310 pivots about a corner of first angled side wall 316into a first releasing position as shown in FIG. 3 (in phantom). Asrelease rod 310 moves toward the first releasing position, handleportion 326 moves away from the adjacent corner portion 110 and middleportion 314 separates away from second angled side wall 318 to moveplunger 300 toward the releasing position.

Alternatively, when handle portion 326 is squeezed toward the adjacentcorner portion 110, release rod 310 pivots about a corner of secondangled side wall 318 into a second releasing position. As release rod310 moves toward the second releasing position, handle portion 324 movesaway from the adjacent corner portion 110 and middle portion 314separates away from first angled side wall 316 to move plunger 300toward the releasing position.

Thus, first angled side wall 316 has a corner that provides a firstfulcrum point about which release rod 310 can pivot and second angledside wall 318 has a corner that provides a second fulcrum point aboutwhich release rod 310 can pivot, thereby allowing either of handleportions 324, 326 to be actuated to unlock back section 50 for pivotingmovement relative to frame 32. In addition, the caregiver or surgeon cansimultaneously grasp one of corner portions 110 of frame member 82 andthe respective handle portion 324, 326 of release rod 310 so that afteractuation of one of handle portions 324, 326, the caregiver or surgeoncan manually pivot back section 50 relative to frame 32 of stretcher 30.

Another releasing assembly 330 is coupled to each extender board 54 sothat when extender boards 54 are in the respective first positions,either releasing assembly 330 can be actuated to actuate release rod 310which releases gas spring 282 allowing back section 50 to pivot relativeto frame 32. The description below of one of releasing assemblies 330 isdescriptive of both releasing assemblies.

Releasing assembly 330 includes a release lever 332 and a plunger rod334 as shown in FIG. 4. A plate 336 is attached to distal end portion132 and mid-size side portion 134 of frame 120 of extender board 54.Release lever 332 includes a middle portion 338 coupled to plate 336 bya pivot pin 340. Release lever 332 also includes an end 344 that engagesplunger rod 334 and a handle portion 342 positioned to lie in closeproximity to corner portion 130 of frame 120 so that corner portion 130and handle portion 342 can be grasped simultaneously when releasingassembly 330 is actuated. A soft handle cover 343 is attached to handleportion 342 to provide a comfortable feel to handle portions 342.

Mid-size side portion 134 of frame 120 is formed to include an internalchamber 346 and plunger rod 334 is received in chamber 346 for slidingmovement. In addition, mid-size side portion 134 of frame 120 is formedto include a slot 348 that provides access to chamber 346. Release lever332 extends through slot 348 so that end 344 of release lever 332 isreceived in chamber 346.

Plunger rod 334 includes a first end 350 engaging end 344 of releaselever 332 within chamber 346. Plunger rod 334 also includes a second end352 spaced apart from first end 350 as shown in FIG. 4. Frame 120includes an end block 354 coupled to mid-size side portion 134 by ascrew 355. End block 354 is formed to include an aperture 356 and secondend 352 of plunger rod 334 extends through aperture 356 into dockingportion 146 of frame 120. Plunger rod 334 is formed to include ashoulder 358 and a coil spring 360 is positioned to lie between shoulder358 and end block 354. Coil spring 360 is maintained in a state ofcompression so that plunger rod 334 is biased toward distal end portion132 of frame 120 and into engagement with end 344 of release lever 332.

Mid-size side portion 134 of frame 120 includes an edge 362 that definesa first end of slot 348. When release lever 332 is unactuated, spring360 acts through plunger rod 334 to bias release lever 332 intoengagement with edge 362. Engagement of release lever 332 with edge 362prevents plunger rod 334 from moving past the position shown in FIG. 4toward distal end portion 132 of frame 120. When release lever 332engages edge 362 releasing assembly 330 is in a locking position.

Movement of handle portion 342 of release lever 332 toward cornerportion 130 of frame 120 in a direction indicated by arrow 364, shown inFIG. 4, causes end 344 of release lever 332 to move in a directionindicated by arrow 366. Movement of end 344 in direction 366 pushesplunger rod 334 in a direction indicated by arrow 368 resulting insecond end 352 of plunger rod moving further into docking portion 146 offrame 120. In addition, movement of plunger rod 334 in direction 368further compresses spring 360.

Portion 134 of frame 120 includes an edge 370 that defines a second endof slot 348. Handle portion 342 can be moved in direction 364 untilrelease lever 332 engages edge 370. Engagement of release lever 332 withedge 370 prevents plunger rod 334 from moving past the position shown inFIG. 4 (in phantom). When release lever 332 engages edge 370 releasingassembly 330 is in a releasing position.

As previously described, when extender board 54 is in the firstposition, docking portion 146 engages post 254 to locate extender board54 in the first position. In addition, when extender board 54 is in thefirst position, mid-size side portion 134 is generally aligned with post254 as shown in FIG. 4. Post 254 is a hollow tube which extends throughan aperture formed in end strut 100 so that portions of post 254 arepositioned to lie on opposite sides of end strut 100. Thus, post 254provides a passage through end strut 100.

A plunger 372 is received inside post 254 for sliding movement relativeto post 254 as shown in FIG. 4. Plunger 372 includes a first end 374 onone side of end strut 100 and a flared second end 376 on the oppositeside of end strut 100. A coil spring 378 is mounted on plunger 372between post 254 and flared second end 376 of plunger 372. Spring 378biases second end 376 of plunger 372 into engagement with straightportion 322 of release rod 310. When extender board 54 is in the firstposition and handle portion 342 of release lever 332 is moved indirection 364 toward corner portion 130 of frame 120 of extender board54, plunger rod 334 moves in direction 368 and second end 352 of plungerrod 334 engages first end 374 of plunger 372 to move plunger 372 in adirection indicated by arrow 380, shown in FIG. 4.

As plunger 372 moves in direction 380, due to actuation of releasingassembly 330, plunger 372 moves release rod 310 into one of itsreleasing positions, thereby releasing gas spring 282 so that theposition of back section 50 can be adjusted. Actuation of releasingassembly 330 coupled to the extender board 54 mounted to first side 40of back section 50 causes first handle portion 324 to move away from theadjacent corner portion 110 of frame member 82 in a direction indicatedby arrow 382 as shown in FIG. 4. Movement of first handle portion 324 indirection 382 causes release rod 310 to pivot about the second fulcrumpoint provided by the corner portion of second angled side wall 318. Asrelease rod 310 pivots about the second fulcrum point, middle portion314 of release rod 310 separates away from first angled side wall 316 ofpivot block 294 to move plunger 300 toward the releasing position.

Actuation of releasing assembly 330 coupled to the extender board 54mounted to second side 42 of back section 50 results in movement ofrelease rod 310 that is a mirror image of the movement of release rod310 described above with reference to actuation of release assembly 330coupled to the extender board 54 mounted to first side 40 of backsection 50. For example, actuation of releasing assembly 330 coupled tothe extender board 54 mounted to second side 42 of back section 50causes release rod 310 to pivot about the first fulcrum point providedby the corner portion of first angled side wall 316 and middle portion314 of release rod 310 separates away from second angled side wall 318of pivot block 294 to move plunger 300 toward the releasing position.

Thus, stretcher 30 includes pivot block 294 and release rod 310 whichcooperate to provide stretcher 30 with a first releasing assembly thatcan be actuated to unlock back section 50 for pivoting movement aboutaxis 92 and stretcher 30 includes a pair of second releasing assemblies330, each of which can be actuated to actuate the first releasingassembly. In addition, the caregiver or surgeon can simultaneously graspcorner portion 130 of the respective frame member 120 and the handleportion 342 of the respective release lever 332 so that after actuationof either of second releasing assemblies 330, the caregiver or surgeoncan manually pivot back section 50 relative to frame 32 of stretcher 30.

As previously described, stretcher 30 includes a head rest 48 coupled toback section 50. Stretcher 30 includes a mounting bracket 384 coupled toback section 50 for pivoting movement about a transverse first pivotaxis 386 and head rest 48 is coupled to mounting bracket 384 forpivoting movement about a transverse second pivot axis 388 as shown inFIGS. 8-10. A first locking mechanism 390 connects a first elbow portion392 of bracket 384 to back section 50 and a second locking mechanism 394connects a second elbow portion 396 of bracket 384 to head rest 48.

First locking mechanism 390 is lockable to prevent bracket 384 frompivoting about axis 386 relative to back section 50 and second lockingmechanism 394 is lockable to prevent head rest 48 from pivoting aboutaxis 388 relative to bracket 384. Thus, when first and second lockingmechanisms 390, 394 are both locked, the position of head rest 48 isfixed relative to back section 50. First locking mechanism 390 isreleasable to allow manual adjustment of bracket 384 about axis 386relative to back section 50 and second locking mechanism 394 isreleasable to allow manual adjustment of head rest 48 about axis 388relative to bracket 384.

A wire grip handle 398 is coupled to head rest 48 as shown, for example,in FIGS. 2 and 8-14. Grip handle 398 includes a pair of side handleportions 400 that extend longitudinally alongside each of sides 140, 142of head rest 48 in spaced-apart relation therewith. Side handle portions400 can be grasped to guide the movement of head rest 48 as the positionof head rest 48 is manually adjusted. Grip handle 398 also includes anend handle portion 410 connecting side handle portions 400. End handleportion 410 can be grasped to help guide the movement of stretcher 30along floor 64.

Head rest 48 includes a bottom plate 412 having a downwardly-facingbottom surface 414 and grip handle 398 includes a rear central branch416 extending from end handle portion 412 and coupling to bottom surface414 of bottom plate 412 as shown in FIG. 11. Grip handle 398 alsoincludes a pair of front branches 418 that couple to bottom surface 414of bottom plate 412. Although side handle portions 400, end handleportion 410, and branches 416, 418 of wire grip handle 398 are shown asbeing a single integral piece, it is within the scope of the inventionas presently perceived for each side handle portion 400 and end handleportion 410 to be separate pieces that are configured to separatelyattach to head rest 48.

Stretcher 30 includes a pair of release buttons 420 coupled to head rest48 and coupled to first and second locking mechanisms 390, 394. Releasebuttons 420 can be moved from a locking position to a releasing positionto simultaneously unlock first locking mechanism 390 and second lockingmechanism 394. Each release button 420 is positioned to lie between oneof side handle portions 400 of grip handle 398 and a corresponding side140, 142 of head rest 48. In addition, each release button 420 includesa thumb-engaging surface 422.

In use, the caregiver or surgeon can grasp side handle portions 400 ofgrip handle 398 with his or her fingers and can actuate release buttons420 by pressing on thumb-engaging surfaces 422 with his or her thumbs tomove release buttons 420 to the releasing position, thereby unlockingfirst and second locking mechanisms 390, 394. When first and secondlocking mechanisms 390, 394 are unlocked, the caregiver or surgeon canuse side handle portions 400 of grip handle 398 to manually move headrest 48 to a desired position relative to back section 50.

After the caregiver or surgeon has moved head rest 48 to the desiredposition, the caregiver or surgeon can remove his or her thumbs from thethumb-engaging surfaces 422 and release buttons 420 will automaticallyreturn to the locking position so that first and second lockingmechanisms 390, 394 simultaneously lock, thereby fixing head rest 48 inthe desired position. Thus, the positioning of side handle portions 400alongside head rest 48 in spaced-apart relation therewith and thepositioning of release buttons 420 between side handle portions 400 andhead rest 48 facilitates the easy unlocking and manual repositioning ofhead rest 48 relative to back section 50.

Head rest 48 can be moved to and locked in an infinite number ofpositions relative to back section 50. For example, bracket 384 and headrest 48 can be locked in a position in which head rest 48 issubstantially aligned with back section 50 as shown in FIG. 8. Bracket384 can pivot downwardly about axis 386 from the position shown in FIG.8 to a lowered position, shown, for example, in FIG. 9. Alternatively,bracket 384 can pivot upwardly about axis 386 from the position shown inFIG. 8 to a raised position, shown, for example, in FIG. 10. Inaddition, head rest 48 can tilt rearwardly about axis 388 from theposition shown in FIG. 8 to a rearward inclined position, shown in FIG.9, or, alternatively, head rest 48 can tilt forwardly about axis 388from the position shown in FIG. 8 to a forward inclined position, shownin FIG. 10.

Frame member 82 of back section 50 includes a first intermediate strut424 connecting side struts 98 between end strut 100 and base strut 84 asshown in FIG. 3. A pair of transversely spaced-apart flanges 426 extendaway from intermediate strut 424. Bracket 384 includes a pair of sideplates 428 and a spacer plate 430 connecting side plates 428 as shown,for example, in FIG. 11. Each plate 428 of bracket 384 includes a firstterminal end portion 432 coupled to a respective flange 426 by a pivotpin 434 which extends transversely between flanges 426. Pivot pin 434cooperates with flanges 426 to define pivot axis 386 about which bracket384 pivots relative to back section 50.

Head rest 48 includes a pair of spaced-apart flanges 436 extendingdownwardly from bottom surface 414 of bottom plate 412 as shown in FIG.11. Each plate 428 of bracket 384 includes a second terminal end portion438 coupled to a respective flange 436 by a pivot pin 440 which extendstransversely between flanges 436. Pivot pin 440 cooperates with flanges436 to define pivot axis 388 about which head rest 48 pivots relative tobracket 384.

First terminal end portion 432 of bracket 384 is coupled to back section50 between end strut 100 of frame 82 and axis 92 as shown in FIGS. 8-10.Side plates 428 of bracket 384 are curved so that sufficient clearanceis established between bracket 384 and end strut 100 of frame 82 of backsection 50 to allow bracket 384 to support head rest 48 at a positionelevated above mattress 44. The clearance between bracket 384 and endstrut also allows gas spring 282 to extend from flanges 286 to pivotblock 294 between side plates 428 of bracket 384 as shown, for example,in FIG. 3. Thus, release rod 310, which is coupled to pivot block 294adjacent to end strut 100 of frame member 82, is coupled to back section50 at a position between terminal end portions 432, 438 of bracket 384.

In a preferred embodiment of stretcher 30, first locking mechanism 390is a gas spring (hereinafter referred to as gas spring 390), although itis within the scope of the invention as presently perceived for lockingmechanism 390 to include any of the locking mechanisms that werementioned above with reference to actuator 282. Gas spring 390 includesa housing 442, a piston (not shown) inside housing 442, and a piston rod444 coupled to the piston and extending out of housing 442. Gas spring390 can be locked so that piston rod 444 can neither extend further outof housing 442 nor retract into housing 442, thereby preventing bracket384 from pivoting about axis 386 relative to back section 50. Gas spring390 can also be released so that the piston and piston rod 444 canextend and retract relative to housing 442, thereby allowing bracket 384to pivot about axis 386 relative to back section 50.

Frame member 82 of back section 50 includes a second intermediate strut446 connecting side struts 98 adjacent to base strut 84 as shown in FIG.3. A pair of flanges 448 extend away from intermediate strut 446 towardend strut 100. Housing 442 of gas spring 390 includes an end 450 coupledto flanges 448 for pivoting movement by a pivot pin 452. Flanges 448 arecoupled to intermediate strut 446 at a slightly off-center location sothat gas spring 390 does not interfere with gas spring 282 as either ofgas springs 390, 282 is operated. As shown, for example, in FIG. 11,piston rod 444 includes an end 454 coupled for pivoting movement toelbow portion 392 of one of side plates 428 by a pivot pin 456.

In a preferred embodiment of stretcher 30, second locking mechanism 394is a spring clutch (hereinafter referred to as spring clutch 394),although it is within the scope of the invention as presently perceivedfor locking mechanism 394 to include any of the locking mechanisms thatwere mentioned above with reference to actuator 282. Spring clutch 394includes a clutch housing 458 and a rod 460 slidably received by clutchhousing 458. Spring clutch 394 also includes a coil gripping spring (notshown) received in clutch housing 458 and defining an interior regionreceiving a portion of rod 460. Spring clutch 394 can be locked so thatthe gripping spring constricts around rod 460 preventing rod 460 fromsliding relative to the gripping spring and clutch housing 458. Springclutch 394 can also be released so that the gripping spring loosens itsgrip on rod 460 allowing rod 460 to slide relative to the grippingspring and clutch housing 458.

A pair of flanges 462 are appended to housing 458 of spring clutch 394as shown in FIG. 11. Flanges 462 are coupled to elbow portions 396 ofside plates 428 by a pivot pin 464 which extends between elbow portions396. Head rest 48 includes a pair of spaced-apart flanges 466 extendingdownwardly from bottom surface 414 of bottom plate 412 as shown in FIG.11. An end 468 of rod 460 is coupled to flanges 466 by a pivot pin 470.Thus, when spring clutch 394 is locked, rod 460 cannot move relative tohousing 458, thereby preventing head rest 48 from pivoting relative tobracket 384, and when spring clutch 394 is released, rod 460 can moverelative to housing 458, thereby allowing head rest 48 to pivot relativeto bracket 384.

As previously described, stretcher 30 includes release buttons 420 thatcan be engaged to simultaneously unlock first and second lockingmechanisms 390, 394. Release buttons 420 are each coupled to oppositeends of pivot pin 440 by an arm 472. Arms 472 are each fixed to pivotpin 440 to rotate about axis 388 therewith. Thus, arms 472 and head rest48 both pivot about axis 388 relative to bracket 384. By having arms 472and head rest 48 both pivot about axis 388, release buttons 420 can beheld in the same orientation relative to head rest 48 as head rest 48 ismoved relative to bracket 384 about axis 388. In addition, if only oneof release buttons 420 is pressed, both release buttons 420 move asresult of the rigid coupling of arms 472 to pivot pin 440.

A transversely-extending tab 474 is appended to one of arms 472 and aplate 476 is appended to bottom plate 412 of head rest 48 as shown inFIG. 11. Plate 476 is bent so that a portion of plate 476 is positionedto lie in confronting relation with tab 474. A first Bowden wire 478includes a sheath 480 extending from plate 476 to gas spring 390 and acable 482 extending from tab 474 to gas spring 390 through sheath 480. Asecond Bowden wire 484 includes a sheath 486 extending from plate 476 tospring clutch 394 and a cable 488 extending from tab 474 to springclutch 394 through sheath 486.

When release buttons 420 are pressed to the releasing position, therebypivoting arms 472 and pivot pin 440 about axis 388, tab 474 is movedaway from plate 476 so that cables 482, 488 are pulled relative tosheaths 480, 486, respectively, in the direction indicated by arrows490, shown in FIG. 11. Movement of cables 482, 488 in respectivedirections 490 actuates mechanisms (not shown) inside of gas spring 390and spring clutch 394, in a manner well known to those skilled in theart, to simultaneously unlock gas spring 390 and spring clutch 394 sothat the position of head rest 48 can be adjusted. When release buttons420 are no longer pressed, gas spring 390 and spring clutch 394automatically lock to pull cables 482, 488 relative to sheaths 480, 486,respectively, in a direction opposite to direction 490 so that tab 474is moved toward plate 476 and release buttons 420 are moved back totheir locking positions adjacent to side handle portions 400 of griphandle 398.

A transversely-extending socket tube 492 having a square-shaped sidewall 494 defining an interior region 496 is coupled to bottom surface414 of bottom plate 412 of head rest 48 as shown in FIG. 11. Socket tube492 has spaced-apart open ends 498 that provide access to interiorregion 496. Socket tube 492 is adapted to allow attachment of a temporalwrist rest assembly 500, a portion of which is shown in FIG. 11, to headrest 48.

Temporal wrist rest assembly 500 includes a transversely-extending rod510 and a first vertical rod 512 appended to an end of rod 510 as shownin FIGS. 11 and 12. Temporal wrist rest assembly 500 also includes asecond vertical rod 514 coupled to first vertical rod 512 fortelescoping movement and a temporal wrist rest 516 coupled to an upperend 518 of second vertical rod 514 for pivoting movement.

Transversely-extending rod 510 can be inserted into interior region 496of socket tube 492 so that temporal wrist rest assembly 500 is mountedto head rest 48. Rod 510 can be inserted into interior region 496through either of open ends 498 of socket tube 492 so that temporalwrist rest assembly 500 is adjacent to side 140 of head rest 48 or sothat temporal wrist rest assembly 500 is adjacent to side 142 of headrest. Rod 510 extends above one of side handle portions 400 and beneathbottom plate 412 of head rest 48 when wrist rest assembly 500 is mountedto head rest 48. The cross-section of transversely-extending rod 510 issquare-shaped so that side wall 494 of socket tube 492 engages rod 510to prevent rod 510 from pivoting relative to socket tube 492.

A threaded cylinder 520 is appended to a bottom corner portion of sockettube 492 and a turn screw 522 is threadedly coupled to cylinder 520.Turn screw 522 can be turned to tighten rod 510 against socket tube 492to prevent transverse movement of temporal wrist rest assembly 500relative to head rest 48. Turn screw 522 can also be turned to loosenrod 510 from socket tube 492 to allow transverse movement of temporalwrist rest assembly 500 relative to head rest 48. Thus, the transverseposition of wrist rest 516 relative to head rest 48 can be adjusted bymoving rod 510 within socket tube 492 to a desired position and thenturn screw 522 can be tightened to lock temporal wrist rest assembly 500in the desired transverse position.

A threaded cylinder 524 is appended to a corner portion of firstvertical tube 512 and a turn screw 526 is threadedly coupled to cylinder524. Turn screw 526 can be turned to tighten second vertical rod 514against first vertical rod 512 to prevent vertical telescoping movementof second vertical rod 514 relative to first vertical rod 512. Turnscrew 526 can also be turned to loosen rod 514 from rod 512 to allowvertical telescoping movement of rod 514 relative to rod 512. Thus, thevertical position of wrist rest 516 relative to head rest 48 can beadjusted by moving rod 514 relative to rod 512 to a desired position andthen turn screw 526 can be tightened to lock wrist rest 516 in thedesired vertical position.

A bracket 528 is appended to wrist rest 516 and couples wrist rest 516to second vertical rod 514. Bracket 528 includes a pair of pivotportions 530 and a stop portion 532 connecting pivot portions 530. Pivotportions 530 are coupled to upper end 518 of second vertical rod 514 bya pivot pin 533. Wrist rest 516 can pivot about pin 533 relative tosecond vertical rod 514 between a first position, shown in FIG. 12, inwhich stop portion 532 of bracket 528 engages one side of rod 514 tosupport wrist rest 516 in the first position and a second position (notshown) in which stop portion 532 of bracket 528 engages an opposite sideof rod 514 to support wrist rest 516 in the second position. When wristrest 516 is in the first position, the surgeon can rest his or herwrists on wrist rest 516 while performing surgery on the patient. Whenwrist rest 516 is in the second position, wrist rest 516 is moved awayfrom head rest 48 so that the surgeon has greater access to the head ofthe patient.

Head rest 48 includes a pair of longitudinally-extending socket tubes534 appended to bottom plate 412 as shown in FIGS. 11-13. Socket tubes534 each include a tube wall 536 defining an interior region 538 asshown best in FIG. 12. Socket tubes 534 each have an open end 540 thatprovides access to interior regions 538 of respective socket tubes 534.Socket tubes 534 are adapted to allow attachment of a wrist restassembly 542 to head rest 48 as shown in FIG. 13.

Wrist rest assembly 542 includes a longitudinally-extending first rod544 and a longitudinally-extending second rod 546. Atransversely-extending end rod 548 is integrally appended to first rod544 and a transversely-extending end socket tube 550 is appended to anend of second rod 546. Wrist rest assembly 542 further includes a firstvertical rod 560 appended to an end portion of rod 548 and extendingupwardly therefrom as shown in FIGS. 13 and 14. An end tube 549 of wristrest assembly 542 is appended to first vertical rod 560 and extendstransversely therefrom. Wrist rest assembly 542 also includes a secondvertical rod 562 coupled to first vertical rod 560 for telescopingmovement and a U-shaped wrist rest 564 coupled to an upper end 566 ofsecond vertical rod 562 for pivoting movement.

End socket tube 550 includes a tube wall 552 defining an interior region554 of end socket tube 550 and a portion of end tube 549 is received ininterior region 554 as shown in FIG. 14. A turn screw 556 couples endtube 549 to end socket tube 550 so that rods 544, 546 are coupledtogether. Turn screw 556 can be rotated about an axis 558 to move endtube 549 relative to end socket tube 550, thereby moving first verticalrod 560 and end rod 548 which moves rod 544 relative to rod 546.

Longitudinally-extending rods 544, 546 can be inserted through open ends540 of respective socket tubes 534 into interior regions 538 so thatwrist rest assembly 542 is mounted to head rest 48. Wrist rest assembly542 can be moved longitudinally relative to head rest 48 to a desiredposition and then turn screw 556 can be turned to tighten rods 544, 546against tube walls 536 of socket tubes 534, thereby locking wrist restassembly 542 from longitudinal movement relative to head rest 48. Turnscrew 556 can also be turned to loosen rods 544, 546 from tube walls 536of socket tubes 534 so that wrist rest assembly 542 can belongitudinally moved relative to head rest 48.

A threaded cylinder 568 is appended to a corner portion of firstvertical tube 560 and a turn screw 570 is threadedly coupled to cylinder568. Turn screw 570 can be turned to tighten second vertical rod 562against first vertical rod 560 to prevent vertical telescoping movementof second vertical rod 562 relative to first vertical rod 560. Turnscrew 570 can also be turned to loosen rod 562 from rod 560 to allowvertical telescoping movement of rod 562 relative to rod 560. Thus, thevertical position of wrist rest 564 relative to head rest 48 can beadjusted by moving rod 562 relative to rod 560 to a desired position andthen turn screw 570 can be tightened to lock wrist rest 564 in thedesired vertical position.

A bracket 572 is appended to wrist rest 564 and couples wrist rest 564to second vertical rod 562. Bracket 572 includes a pair of pivotportions 574 and a stop portion 576 connecting pivot portions 574. Pivotportions 574 are coupled to upper end 566 of second vertical rod 562 bya pivot pin 578. Wrist rest 564 can pivot about pin 578 relative tosecond vertical rod 562 between a first position, shown in FIG. 13, inwhich stop portion 576 of bracket 572 engages one side of rod 562 tosupport wrist rest 564 in the first position and a second position (notshown) in which stop portion 576 of bracket 572 engages an opposite sideof rod 562 to support wrist rest 564 in the second position.

Wrist rest 564 includes a pair of side portions 580 and an end portion582 connecting side portions 580. When wrist rest 516 is in the firstposition, side portions 580 extend above sides 140, 142 of head rest 48away from end portion 582 toward patient-support deck 34. The surgeoncan rest his or her wrists on side portions 580 and end portion 582 ofwrist rest 564 while performing surgery on the patient when wrist rest564 is in the first position. When wrist rest 564 is in the secondposition, wrist rest 564 is moved away from head rest 48 so that thesurgeon has greater access to the head of the patient.

As previously described, end tube 549 is received in interior region 554of end socket tube 550 and turn screw 556 is coupled to both end tube549 and end socket tube 550. An end plug 584 is inserted into aninterior region 586 of end tube 549 and is fixed to end tube 549 asshown in FIG. 14. End socket tube 550 includes an end wall 588 adjacentto end plug 584. End wall 588 is formed to include an aperture 590 andend plug 584 is formed to include a threaded aperture 592.

Turn screw 556 includes a knob 594 and a threaded screw portion 596extending away from knob 594 as shown in FIG. 14. Threaded screw portion596 extends through aperture 590 formed in end wall 588 and is receivedby threaded aperture 592 formed in end plug 584 so that threaded screwportion 596 of turn screw 556 threadedly engages end plug 584. As knob594 is rotated about axis 558, threaded screw portion 596 rotatesrelative to end plug 584 and end wall 588 about axis 558.

Knob 594 includes a tube-engaging surface 598 that can be moved intoengagement with end wall 588 of end socket tube 550 as shown in FIG. 14.When rods 544, 546 are received in respective socket tubes 534, knob 594can be turned in a tightening direction, indicated by arrow 600, shownin FIG. 13, until tube-engaging surface 598 of knob 594 engages end wall588. Further rotation of knob 594 in direction 600, after initialengagement between tube-engaging surface 598 and end wall 588, causesthreaded screw portion 596 to rotate within end plug 584 but engagementbetween tube-engaging surface 598 and end wall 588 prevents axialmovement of threaded screw portion 596 along axis 558. Thus, aftertube-engaging wall 598 engages end wall 588, rotation of knob 594 indirection 600 pulls end plug 584 and end tube 549 toward end wall 588which causes rods 544, 546 to bind against tube walls 536 of sockettubes 534, thereby locking wrist rest assembly 542 from longitudinalmovement relative to head rest 48.

Knob 594 can be turned in a loosening direction, indicated by dottedarrow 610, shown in FIG. 13, until rods 544, 546 are once again free tomove relative to socket tubes 534 of head rest 48. After rods 544, 546are loosened from socket tubes 534, wrist rest assembly 542 can becompletely decoupled from head rest 48. End socket tube 550 includes anedge 612 defining a slot 614 as shown in FIG. 14. A post 616 is coupledto end tube 549 and is received in slot 614 so that, when wrist restassembly 542 is decoupled from head rest 48, post 616 engages edge 612to limit the amount by which end socket tube 550 and rod 546 can pivotrelative to end tube 549 about axis 558.

Each of side portions 580 of wrist rest 564 can include open ends 618that allow auxiliary medical equipment to be attached to wrist rest 564.For example, an air manifold assembly 620, shown in FIGS. 15 and 16, canbe attached to wrist rest 564. Air manifold assembly 620 includes endcaps 622 that mount to respective open ends 618 of side portions 580.Air manifold assembly 620 also includes a flexible tube 624 extendingfrom each end cap 622. Flexible tubes 624 each couple to an end of acylindrical air manifold 626 of air manifold assembly 620.

Air manifold 626 can include a center wall 628 that partitions airmanifold 626 into an oxygen delivery side 630 and a carbon dioxideremoval side 632. Center wall 628 divides an interior region of manifold626 into two separate side-by-side interior regions. Sides 630, 632 ofair manifold 626 are each formed to include a plurality of pores 634that open into the respective side-by-side interior regions of airmanifold 626. Thus, some of pores 634 are associated with oxygendelivery side 630 of air manifold 626 and some of pores 634 areassociated with carbon dioxide removal side 632 of air manifold 626.

Each end cap 622 includes a tube connector 640 depending downwardlytherefrom. An oxygen delivery hose 636 can be coupled to one of tubeconnectors 640 and a carbon dioxide removal hose 638 can be coupled tothe other of tube connectors 640. End cap 622 associated with oxygendelivery hose 636, oxygen delivery side 630 of air manifold 626, and theflexible tube 624 therebetween all include internal passageways (notshown) in fluid communication with one another so that oxygen suppliedthrough oxygen delivery hose 636 can flow through the internalpassageways and out of the pores 634 associated with oxygen deliveryside 630 of air manifold 626. Similarly, end cap 622 associated withcarbon dioxide removal hose 638, carbon dioxide removal side 632 of airmanifold 626, and the flexible tube 624 therebetween all includeinternal passageways (not shown) in fluid communication with one anotherso that, when suction is applied to carbon dioxide removal hose 638, theair in the vicinity of pores 634 associated with carbon dioxide removalside 632 of air manifold 626, can flow through the internal passagewaysand into carbon dioxide removal hose 638.

Flexible tubes 624 can be manipulated into an infinite number oforientations relative to wrist rest 564 so that air manifold 626 is at adesired position relative to the head of the patient supported by headrest 48. For example, it may be desirable to position air manifold 626so that oxygen delivered to the patient through manifold 626 is directedtoward the nose and mouth of the patient as shown in FIG. 16. Wrist rest564 and air manifold assembly 620 can pivot away from the head of thepatient, for example, to an intermediate out-of-the-way position asshown in FIG. 15 (in phantom) so that the access to the head of thepatient is increased.

Flexible tubes 624 have sufficient stiffness to support a surgical drape642 over the head of the patient to create a tented environment as shownin FIG. 16. Drape 642 can include a “sticky” side that adheres to thehead of the patient and that adheres to the portions of air manifoldassembly 620 and wrist rest 564 that support drape 642 above the head ofthe patient. The surgeon can cut a hole in drape 642 to expose the partof the head of the patient on which surgery is to be performed. Evenwhen wrist rest 564 is covered by drape 642, the surgeon can rest his orher wrists on side and end portions 580, 582 of wrist rest 564.

As previously described, head rest 48 carries a head cushion 52 thatsupports the head of the patient. Head rest 48 includes a pair ofspaced-apart side plates 644 angling upwardly from respective sockettubes 534 to define a head cushion-receiving space 646 therebetween asshown best in FIGS. 12 and 13. Although bottom plate 412, socket tubes534, and side plates 644 of head rest 48 are shown as being a singleintegral piece, it is within the scope of the invention as presentlyperceived for some or all of these components to be separate pieces thatare fastened together. For example, each socket tube 534 and theassociated side plate 644 could be an extruded piece that fastens to arespective side of a single bottom plate 412. Other divisions of headrest 48 into separate pieces that fasten together are also possible.

Head cushion 52 includes angled side surfaces 648 and a bottom surface(not shown). When head cushion 52 is received in head cushion-receivingspace 646, the bottom surface of head cushion 52 engages bottom plate412 of head rest 48 and portions of side surfaces 648 engage companionside plates 644 so that head cushion 52 securely mates with head rest 48within head cushion-receiving space 646. Fasteners (not shown), such ashook-and-loop fastener strips, can be attached to head cushion 52 andhead rest 48 so that head cushion 52 is more securely coupled to headrest 48.

Head cushion 52 includes an upwardly-facing concave surface 650 thatdefines a head cradle 652 as shown, for example, in FIG. 11. Head cradle652 is adapted to receive the head of the patient and concave surface650 helps to stabilize the head of the patient during surgery. A cradleinsert 654 can be coupled to head rest 48 to fill head cradle 652 whenstretcher 30 is being used to transport the patient before and aftersurgery. Cradle insert 654 includes a downwardly-facing convex surface656 that engages concave surface 650 of head cushion 52 when cradleinsert 654 is inserted into head cradle 652.

Head cushion 52 includes a pair of upwardly-facing substantially planarsurfaces 658, each of which extends between a respective upper edge 660of concave surface 650 and the corresponding side surface 648. Cradleinsert 654 includes a pair of fastening flaps 662, each of whichincludes a first portion 664 that extends over one of planar surfaces658 when cradle insert 654 is received in head cradle 652, and each ofwhich includes a second portion 666 that can be folded downwardly fromits associated first portion 664 into engagement with side plates 644 ofhead rest 48.

A hook-and-loop fastener strip 668 is fixed to each second portion 666of fastening flaps 662 and a companion hook-and-loop fastener strip 670is fixed to an outer surface 672 of each side plate 644 of head rest 48.When cradle insert 654 is inserted into head cradle 652, fastening flaps662 can be folded relative to head cushion 52 and head rest 48 so thatstrips 668 engage companion strips 670 to firmly secure cradle insert654 in head cradle 652. Cradle insert 654 includes an upwardly-facingsubstantially planar surface 674 that is positioned to lie above convexsurface 656. Surface 674 supports the head of the patient when cradleinsert 654 is received in head cradle 652 of head cushion 52.

An alternative embodiment head cushion 676 is shown in FIGS. 17-19. Headcushion 52 can be removed from head cushion-receiving space 646 and headcushion 676 can be inserted into head cushion-receiving space 646 toreplace head cushion 52 as indicated by double arrow 678 shown in FIG.17. Compared to head cushion 52, head cushion 676 provides increasedstabilization of the head of the patient, which is desirable during somehead surgeries.

Head cushion 676 is a two-chamber vacuum pad (hereinafter referred to asvacuum pad 676) that includes a foam pad 680 in one of the chambers anda plurality of plastic beads 682 in the other of the chambers as shownin FIG. 19. Vacuum pad 676 includes a bag 684 having three sheets thatare sealed together to define the chambers. In a preferred embodiment,bag 684 includes a first outer sheet made of Penn Nyla P079 material, asecond outer sheet made of 15 mil urethane, and a middle sheet made of 6mil urethane. Foam pad 680 is positioned to lie between the middle sheetand the first outer sheet. Plastic beads 682 are contained within aplurality of tubes 683 that are connected to form a bead pad. Some oftubes 683 are orthogonal to other of tubes 683 as shown in FIG. 19. Thebead pad is positioned to lie between the middle sheet and the secondouter sheet of bag 684.

Vacuum pad 676 includes a tube connector port 686 and a relief valve 688as shown in FIG. 17. The bead pad which contains beads 682 is airpermeable and the middle and second sheets of bag 684 are airimpermeable. A hose (not shown) can be attached to tube connector port686 and suction can be applied to the hose to draw air out of the secondchamber and out of the bead pad through tube connector port 686. Drawingair out of the second chamber and bead pad causes beads 682 to becompressed together, thereby placing vacuum pad 676 in a rigid state.

When suction is not applied to the hose, air is permitted to enter thesecond chamber so that beads 682 are not compressed together and vacuumpad 676 is in a non-rigid state. In addition, relief valve 688 can bemanually pressed so that air is permitted to enter the second chamber,thereby placing vacuum pad 676 in the non-rigid state. Pressing reliefvalve 688 places vacuum pad 676 in the non-rigid state even when suctionis applied to the hose connected to tube connector port 686.

When vacuum pad 676 is in the non-rigid state, vacuum pad 676 isformable into an infinite number of configurations. For example, vacuumpad 676 can be formed from a flat uncupped configuration, shown in FIGS.18 and 19, into a cupped configuration, shown in FIG. 17. Vacuum pad 676has spaced-apart side wall portions 690 and a bottom portion 692connecting side wall portions 690. Vacuum pad 676 includes ahook-and-loop fastener strap 694 extending away from one of side wallportions 690 and vacuum pad includes a companion hook-and-loop fastenerstrip (not shown) fixed to the other of side wall portions 690. Aportion of strap 694 can be attached to the companion strip to help holdvacuum pad 676 in the cupped configuration as shown in FIG. 17.

When vacuum pad 676 is in the cupped configuration and carried by headrest 48, bottom portion 692 of vacuum pad 676 rests upon bottom plate412 of head rest 48 and spaced-apart side wall portions 690 are adjacentto side plates 644 of head rest 48. Vacuum pad 676 includes edges 696that face substantially upwardly when vacuum pad 676 is in the cuppedconfiguration to provide a wrist rest surface 698 on which the wrists ofthe surgeon can rest during surgery. Edges 696 of side walls 690 areformable when vacuum pad 676 is in the non-rigid state. If the surgeonwishes to change the shape of wrist rest surfaces 698 during surgerywhen vacuum pad 676 is in the rigid state, the surgeon can press reliefvalve 688 to place vacuum pad 676 in the non-rigid state and then formedges 686 until wrist rest surfaces 698 are fashioned into the desiredshape. The surgeon can then release relief valve 688 and vacuum pad 676will return to the rigid state having wrist rest surfaces 698 fixed inthe desired shape.

As previously described, stretcher 30 includes pedal assembly 74 whichincludes yoke 76 and flip-over pedal 78 coupled to yoke 76 for pivotingmovement, as shown in FIGS. 20-23. Flip-over pedal 78 has a firstorientation relative to yoke 76 in which distal end portion 80 offlip-over pedal is on one side of yoke 76, as shown in FIGS. 20-22, andflip-over pedal 78 has a second orientation relative to yoke 76 in whichdistal end portion 80 of flip-over pedal 76 is on the other side of yoke76, as shown in FIG. 23, and as also previously described.

A bottom end 700 of yoke 76 is fixed to brake-steer shaft 70 and a topend 710 of yoke 76 is formed to include a pair of spaced-apart pivotportions 712 as shown in FIG. 20. Yoke 76 includes a stop portion 714connecting pivot portions 712. Flip-over pedal 78 has a proximal end 716coupled to pivot portions 712 of yoke 76 above stop portion 714 by apivot pin 718. Pivot pin 718 cooperates with pivot portions 712 todefine a pivot axis 720 about which flip-over pedal 78 can pivotrelative to yoke 76.

Brake-steer shaft 70 is coupled to the lower frame of stretcher 30 forpivoting movement about a pivot axis 722. Axis 720 of flip-over pedal 78is spaced apart from, and is substantially parallel with, axis 722 ofbrake-steer shaft 70. As brake-steer shaft 70 is moved between thesteering and braking positions, axis 720 is always at a higher elevationabove floor 64 than is axis 722 as shown in FIGS. 21-23. Thus, yoke 76offsets flip-over pedal 78 upwardly to occupy a range of positions thatis at a higher elevation relative to floor 64 than would be the case ifflip-over pedal were connected to brake-steer shaft 70 to rotate aboutaxis 722. Having flip-over pedal 78 at this heightened elevationincreases the amount of room available on floor 64 in the vicinity ofpedal assembly 74 for medical devices (not shown), such as foot pedalcontrollers used during surgery to operate associated medical equipment.

Brake-steer shaft 70 has a neutral position midway between the brakingand steering positions, shown in FIGS. 20 and 21, in which yoke 76 is inan upright vertical orientation having axis 720 over axis 722. Whenbrake-steer shaft 70 is in the neutral position, the center wheel isspaced apart from floor 64 and casters 62 are free to rotate and swivel.

Flip-over pedal 78 includes a rod 724 that connects distal end portion80 to proximal end 716. Rod 724 is bent at the middle so that distal endportion 80 of flip-over pedal 78 is spaced apart from shroud 60 asufficient distance to allow the caregiver or surgeon to step on distalend portion 80 without interference from shroud 60.

When flip-over pedal 78 is in the first orientation, one side of rod 724engages stop portion 714 of yoke 76 and when flip-over pedal 78 is inthe second orientation, an opposite side of rod 724 engages stop portion714 of yoke 76. Engagement of rod 724 with stop portion 714 supportsflip-over pedal 78 in the respective first and second orientations. Stopportion 714 of yoke 76 is formed so that flip-over pedal 78 rotatesabout axis 720 relative to yoke 76 through an angle of one hundredeighty degrees (180°) when pivoted between the first and secondorientations.

When flip-over pedal 78 is in the first orientation, brake-steer shaft70 can be rotated from the neutral position, shown in FIG. 21, in aclockwise direction 726 to the steering position, shown in FIG. 22, byapplication of a downward force to distal end portion 80 of flip-overpedal 78. The downward force on distal end portion 80 is transmittedthrough flip-over pedal 78 and yoke 76 to brake-steer shaft 70. Yoke 76is in a first tilted orientation when brake-steer shaft 70 is in thesteering position.

When brake-steer shaft 70 is in the steering position having yoke 76 inthe first tilted orientation, flip-over pedal 78 can be pivoted from thefirst orientation, shown in FIG. 22 (in solid), to the secondorientation, shown in FIG. 22 (in phantom). When brake-steer shaft 70 isin the steering position, distal end portion 80 is spaced apart fromfloor 64 by a first distance 728 if flip-over pedal 78 is in the firstorientation and distal end portion 80 is spaced apart from floor 64 by asecond distance 730 if flip-over pedal 78 is in the second orientation.Second distance 730 is larger than first distance 728 so that more roomis available on floor 64 in the vicinity of pedal assembly 74 whendistal end portion 80 is spaced apart from floor 64 by second distance730.

When flip-over pedal 78 is in the second orientation while brake-steershaft 70 is in the steering position, brake-steer shaft 70 can berotated from the steering position, shown in FIG. 22, in acounterclockwise direction 732 through the neutral position to thebraking position, shown in FIG. 23, by application of a downward forceto distal end portion 80 of flip-over pedal 78. The downward force ondistal end portion 80 is transmitted through flip-over pedal 78 and yoke76 to brake-steer shaft 70. Yoke 76 is in a second tilted orientationwhen brake-steer shaft 70 is in the braking position.

When brake-steer shaft 70 is in the braking position having yoke 76 inthe second tilted orientation, flip-over pedal 78 can be pivoted fromthe second orientation, shown in FIG. 23 (in solid), back to the firstorientation, shown in FIG. 23 (in phantom). When brake-steer shaft 70 isin the braking position, distal end portion 80 is spaced apart fromfloor 64 by a third distance 734 if flip-over pedal 78 is in the secondorientation and distal end portion 80 is spaced apart from floor 64 by afourth distance 736 if flip-over pedal 78 is in the first orientation.Fourth distance 736 is larger than third distance 728 so that more roomis available on floor 64 in the vicinity of pedal assembly 74 whendistal end portion 80 is spaced apart from floor 64 by fourth distance736.

Thus, flip-over pedal 78 can be selectively moved to the first andsecond orientations relative to yoke 76 and a downward force can beapplied to distal end portion 80 of flip-over pedal 78 to movebrake-steer shaft between the steering, neutral, and braking positionsso that the braking of casters 62 and the position of the center wheelis controlled in a desired manner. Stretcher 30 includes indicia 738affixed to shroud 60 for indicating the position of brake-steer shaft70. After brake-steer shaft 70 has been moved to the desired position,flip-over pedal 78 can be moved to a position that maximizes theavailability of room on floor 64 in the vicinity of pedal assembly 74.

Although the invention has been described in detail with reference tocertain preferred embodiments, variations and modifications exist withinthe scope and spirit of the invention as described and as defined in thefollowing claims.

What is claimed is:
 1. An apparatus for supporting a patient, theapparatus comprising a frame, a patient-support deck coupled to theframe and configured to support the patient, a head rest coupled to thepatient-support deck, and a vacuum pad supported by the head rest andconfigured to support the head of the patient, the vacuum pad having anon-rigid state wherein the vacuum pad is formable and a rigid statewherein the vacuum pad is non-formable, the vacuum pad having side wallswith top edges positioned to lie at an elevation above the head rest,the top edges of the vacuum pad providing a wrist rest surface that isformable when the vacuum pad is in the non-rigid state.
 2. The apparatusof claim 1, wherein the head rest includes a bottom plate andspaced-apart side plates extending upwardly from the bottom plate, theside walls of the vacuum pad are positioned to lie adjacent torespective side plates, and the vacuum pad includes a bottom portionthat rests upon the bottom plate of the head rest.
 3. The apparatus ofclaim 1, wherein the vacuum pad includes a strap coupled to one of theside walls, the strap is attachable to the other of the side walls tohold the vacuum pad in a cupped configuration, and the strap isdetachable from the other of the side walls allowing the vacuum pad tobe formed into a flat uncupped configuration.
 4. The apparatus of claim1, wherein the vacuum pad includes a tube connector port to whichsuction can be applied to place the vacuum pad in the rigid state andthe vacuum pad includes a relief valve that can be pressed to place thevacuum pad in the non-rigid state.
 5. A vacuum pad suitable for use witha head rest of a stretcher, the vacuum pad being configured to supportthe head of a patient supported on the stretcher, the vacuum pad havinga non-rigid state wherein the vacuum pad is formable and a rigid statewherein the vacuum pad is non-formable, the vacuum pad having side wallswith top edges positioned to lie at an elevation above the head rest,the top edges of the vacuum pad providing a wrist rest surface that isformable when the vacuum pad is in the non-rigid state.
 6. The vacuumpad of claim 5, wherein a bottom portion of the vacuum pad rests upon abottom plate of the head rest, and wherein the side walls of the vacuumpad are positioned to lie adjacent to respective side plates of the headrest extending upwardly from the bottom plate of the head rest.
 7. Thevacuum pad of claim 5, including a strap coupled to one of the sidewalls of the vacuum pad, wherein the strap is attachable to the other ofthe side walls to hold the vacuum pad in a cupped configuration, andwherein the strap is detachable from the other of the side wallsallowing the vacuum pad to be formed into a flat uncupped configuration.8. The vacuum pad of claim 5, including a tube connector port to whichsuction can be applied to place the vacuum pad in the rigid state, andincluding a relief valve that can be pressed to place the vacuum pad inthe non-rigid state.